A universal personal communication system is a system enabling anyone to communicate instantly with anyone else anywhere in the world. One of the crucial problems of such a system would be locating millions of moving customers in an efficient manner. The existing techniques for locating moving customers in the system are paging and registration using a central database. Considering the large number of customers in a global system, the first technique, if applied without knowledge of the location of the customers is impractical. The registration technique, which records all the movements of customers in a central database, is also impractical because the task of keeping track of such a huge number of users would be immense. Thus, a need exists for a system for efficiently tracking customers in a universal personal communication system.